1. Field of the Invention
The present invention relates to a control system for an internal combustion engine with an associated decompression device designed to prevent or reduce vibration of the engine.
More particularly, the present invention relates to a control system for an internal combustion engine with an associated decompression device adapted to prevent or reduce vibration when the engine is cranked and stopped, the engine being mounted on an electric vehicle and operable to drive an onboard generator/electric motor.
2. Description of the Related Art
A conventional automatic decompression device for an internal combustion engine is disclosed in Japanese utility model publication No. 6-10107.
In this conventional art device, a camshaft has an axial bore to receive a slide pin. The slide pin has a tapered front end. As the engine starts, the slide pin is moved in one direction under the action of a spring. This causes the tapered front end of the slide pin to be forced into contact with the tapered hole of a decompression pin. Then, the decompression pin slightly projects from the surface of a cam to cause opening of intake and exhaust valves. This enables a reduction in the pressure within a combustion chamber.
As engine speed increases, a centrifugal weight enables the slide pin to be moved in the other direction against the action of the spring. The decompression pin is then withdrawn from the cam surface to move the intake and exhaust valves from their open condition to a closed condition.
Another decompression device is known from Japanese laid-open patent publication No. 5-305824.
In this known art device, an engine cylinder is provided with a decompression valve in addition to inlet and exhaust valves. No supply of fuel takes place when the decompression valve is open.
An electric vehicle is now in use and typically includes a battery. The battery is charged by an external source or by an onboard generator. However, the latter means or onboard generator suffers from the following problems.
The electric vehicle is typically less vibrated and noisy than a vehicle with a gasoline engine. However, when a generator is mounted on the electric vehicle, a generator drive engine is subject to vibration and resultant noise. This is particularly true when the engine is cranked and stopped, and presents a major problem. Vibration and noise when the engine is cranked and stopped deteriorate the comfort of persons in and around the electric vehicle.
The inventors have attempted to reduce vibration and noise when an engine is cranked and stopped, in the event that the engine is used in an electric vehicle to drive an onboard generator.
It is an object of the present invention to provide a control system for an internal combustion engine with an associated decompression device, the system being used in an electric vehicle with a generator/electric motor mounted thereon for better controlling vibration and exhaust emissions when the engine is cranked and stopped.